1. Technical Field
The present invention relates to a line type liquid discharge apparatus, a control method of the line type liquid discharge apparatus, a device driver for the line type liquid discharge apparatus, and a printing system, and particularly relates to a line type liquid discharge apparatus which forms dots by impacting a liquid onto a recording medium without scanning a line type liquid discharge head in a width direction of the recording medium, a control method of the line type liquid discharge head, and a control method of the line type liquid discharge apparatus.
2. Related Art
Examples of an ink jet type recording apparatus (a printer) which is a type of a liquid discharge apparatus include a so-called serial type printer which feeds out the recording medium (an impacted object) such as recording paper in the direction orthogonal to a main scanning direction so as to sequentially execute sub scanning on the recording medium while reciprocating an ink jet type recording head which has a shorter width than that of the recording medium in the main scanning direction, and discharges ink from a nozzle of a recording head to record an image or the like on the recording medium. In the printer with such a configuration, when a solvent component of the ink from the nozzle is evaporated and thus the ink is thickened during a recording process (or referred to as a printing process), a flushing operation for discharging the thickened ink from the nozzle is executed. Since the flushing operation is a well-known art, the detailed description will be omitted, but in short, the recording process is stopped due to some reasons that a predetermined time has elapsed during the recording process, or a certain condition is established by monitoring a thickened state in the nozzle, and then ink from the nozzle is discharged in an area (a flushing point) in which the flushing is executed, that is, clearly flushed.
In addition, as a printer, a so-called line type printer which is provided with a recording head (a line type liquid discharge head) which includes a plurality of head unit groups, and in which the entire length of a nozzle group which is formed of the plurality of head unit groups in the width direction of the recording medium corresponds to the maximum recording width of the recording medium which is available in the printer, and executes recording with respect to the recording medium only by transporting the recording medium without scanning the recording head in the width direction of the recording medium, has been also proposed. With such a configuration, it is not necessary to move the recording head in the main scanning direction, and it is possible to shorten a recording time compared to the serial type printer.
However, in the above-described line type printer, as the serial type printer, it is difficult to execute the flushing operation by moving the recording head to the flushing point during the recording process. In relation to such a problem, various configurations have been proposed as a method of eliminating the thickening of ink. For example, in JP-A-2003-159785, a configuration of providing an area for flushing on the outside of an area in which contents such as an image or text on the recording medium, that is, on a margin area, and then executing the flushing in the area is proposed. In addition, in JP-A-2013-107207, a configuration of inconspicuously executing flushing an area on which contents such as an image or text on the recording medium are printed is also proposed.
However, in the former configuration, flushing traces remain on the margin area, and but depending of the use, this flushing traces are undesirable to remain in some cases. In addition, in the latter configuration, even though the flushing is inconspicuously executed, there is a concern of the influence on the image quality in terms of the use where higher image quality such as photographic image quality is requested. Furthermore, in the inconspicuous amount of the flushing with respect to the image, there is a concern in that the thickening of ink is not eliminated. Then, in a case where the thickening of ink is progressed, the thickening of ink is easily increased particularly when forming relatively small dots, and thus impact position deviation, a decrease in the amount of ink, and the like occur, as a result, the image quality of a recorded image or the like is likely to be degraded.